What are some tools that changed your leatherwork?

[Kenzi]

What tools helped enhance your leatherwork? Different types of knives, stamps, etc.? I am a intermediate leather worker, I believe that I still have lots of improvement to do and I am wondering what tools I can use to help me achieve this.

[Mablung]

My absolute favorite tool, and the only one that is not a relatively inexpensive Tandy buy, is my vintage (120 years +) C.S. Osborne round knife.  5.5" inches from point to point that I got for a song on eBay.  I have the tools and know-how to restore the edge, so I sharpened it myself.  I love that knife and do everything with it, from rough cutting to skiving to fine trimming.  The blade is thin, so the whole thing is light and very agile.  Next thing I'd like to upgrade is my stitching awl, but my Tandy Pro one still does the trick for what I'm doing.

But frankly, halfway decent beginner tools will serve you very well for a long time.  The biggest thing to work on, IMO, is technique.  I'm right there at the same stage of skill as you, and I don't think my skill has equaled or surpassed the quality of my tools.